cpan2dsc: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/cpan2dsc - from package: dh-make-perl

You may install the required package with command apt-get install {package}

Error in other languages:
cpan2dsc: bevel nie gevind nie
cpan2dsc: comandă negăsită
cpan2dsc: comando não encontrado
cpan2dsc: commande introuvable
cpan2dsc: command not found
cpan2dsc: käsku ei ole
cpan2dsc: không tìm thấy lệnh
cpan2dsc: komanda nerasta
cpan2dsc: Kommando nicht gefunden.
cpan2dsc: kommandot finns inte
cpan2dsc: komut yok
cpan2dsc: nie znaleziono polecenia
cpan2dsc: níor aimsíodh an t-ordú
cpan2dsc: no se encontró la orden
cpan2dsc: no s'ha trobat l'ordre
cpan2dsc: opdracht niet gevonden
cpan2dsc: parancs nem található
cpan2dsc: perintah tidak ditemukan
cpan2dsc: príkaz nenájdený
cpan2dsc: příkaz nenalezen
cpan2dsc: команда не найдена
cpan2dsc: командата не е открита
cpan2dsc: 命令找不到
cpan2dsc: コマンドが見つかりません